Guide in the morning leaving ship (5)
I believe the answer is:
steer
'guide' is the definition.
(synonyms)
'morning leaving ship' is the wordplay.
'morning' becomes 'am'.
'leaving' indicates named letters should be taken away.
'ship' becomes 'steamer' (steamer is a kind of ship).
'steamer' with 'am' taken away is 'STEER'.
'in the' is the link.
(Other definitions for steer that I've seen before include "farm animal" , "What cowboys try to do to" , "member of herd" , "Guide; bullock" , "Control movement" .)